EPiServer - not rendering the custom property in Edit mode.

I've been scratching my head bald regarding this issue and I am left blank.

I have a PageType, containing a custom property which is directly copied from the AlloyDemo.

    [BackingType(typeof(PropertyStringList))]
    [Display(Order = 305)]
    [UIHint(Global.SiteUIHints.Strings)]
    [CultureSpecific]
    public virtual string[] Address { get; set; }

The BackingType PropertyStringList class looks like this:

[EditorHint(Global.SiteUIHints.Strings)]
[PropertyDefinitionTypePlugIn(Description = "String List", 
DisplayName = "String List")]
public class PropertyStringList : PropertyLongString
{
    protected String Separator = "\n";

    public String[] List
    {
        get
        {
            return (String[])Value;
        }
    }

    public override Type PropertyValueType
    {
        get
        {
            return typeof(String[]);
        }
    }

    public override object SaveData(PropertyDataCollection properties)
    {
        return LongString;
    }

    public override object Value
    {
        get
        {
            var value = base.Value as string;

            if (value == null)
            {
                return null;
            }

            return value.Split(Separator.ToCharArray(),        
    StringSplitOptions.RemoveEmptyEntries);
        }
        set
        {
            if (value is String[])
            {
                var s = String.Join(Separator, value as String[]);
                base.Value = s;
            }
            else
            {
                base.Value = value;
            }

        }
    }

    public override IPropertyControl CreatePropertyControl()
    {
        //No support for legacy edit mode
        return null;
    }
}

When I run the site, it renders (in Edit mode) the property Address like this:

Rendering fail, which is a button And when I click the button I get this: Null Reference Exception in a popup

I seriously have no clue why this is happening. Could somebody explain?

Regards, Chris

You are missing the editor descriptor. Check out "StringListEditorDescriptor.cs" in the Alloy project. You'll also need the client resources -the StringList dojo script. And you also need to register this module.config